The morphology of the Welsh language shows many characteristics perhaps unfamiliar to speakers of English or continental European languages like French or German, but has much in common with the other modern Insular Celtic languages: Irish, Scottish Gaelic, Manx, Cornish, and Breton. Welsh is a moderately inflected language. Verbs conjugate for person, tense and mood with affirmative, interrogative and negative conjugations of some verbs. A majority of prepositions inflect for person and number. There are few case inflections in Literary Welsh, being confined to certain pronouns.
Modern Welsh can be written in two varieties – Colloquial Welsh or Literary Welsh. The grammar described on this article is for Literary Welsh.
Initial consonant mutation
Initial consonant mutation is a phenomenon common to all Insular Celtic languages (there is no evidence of it in the ancient Continental Celtic languages of the early first millennium). The first consonant of a word in Welsh may change depending on grammatical context (such as when the grammatical object directly follows the grammatical subject), when preceded by certain words, e.g. , , and or when the normal word order of a sentence is changed, e.g. , "I have a house".
Welsh has three mutations across four paradigms: the soft mutation (), the nasal mutation (), and the aspirate (or spirant) mutation (); and the mixed mutation () where the aspirate mutation is applied where possible, else the soft mutation is applied. These are represented in writing, as shown in the table below along with their corresponding IPA symbols.
{| class="wikitable" ! Radical ! Soft ! Nasal ! Aspirate ! Mixed |- | p | b | mh | ph | ph |- | t | d | nh | th | th |- | c | g | ngh | ch | ch |- | b | f | m | | f |- | d | dd | n | | dd |- | g | ∅* | ng | | ∅* |- | m | f
| f |- | ll | l
| l |- | rh | r
| r
A blank cell indicates no change.
For example, the word for "stone" is , but "the stone" is (soft mutation), "my stone" is (nasal mutation) and "her stone" is (aspirate mutation).
* The soft mutation for g is the simple deletion of the initial sound. For example, "garden" becomes "the garden". But this can behave as a consonant under certain circumstances, e.g. "gellir" (one can) becomes "ni ellir" (one cannot) not "*nid ellir". This however also stands alongside (), but () not *.
Soft mutation
The soft mutation (Welsh: ) is, by far, the most common mutation in Welsh. When words undergo soft mutation, the general pattern is that voiceless plosives become voiced plosives, voiced plosives become voiced fricatives, and voiceless liquids becomes voiced. The full list is shown in the above table.
Common situations where the full soft mutation occurs are as follows – this list is by no means exhaustive:
adjectives (and nouns used adjectivally) qualifying feminine singular nouns words immediately following the prepositions "for, about", "on", "to", / "under", / "over", / "through", "without", "until", "by", "at", "to, for", "of, from" nouns used with the number two ( / ) nouns following adjectives (N.B. most adjectives follow the noun) nouns after the possessives , informal singular "your", and when it means "his" an object of an inflected verb, except if it has the article the second element in many compound words the first letter of adverbs and adverbial phrases, especially of time (e.g. "every day" cf. "every"; N.B. itself does not cause mutation) the second element in many adverbial phrases, e.g. "completely different" when an adverbial phrase comes between two elements, the second element is mutated (e.g. "it is necessary to go" becomes "it is necessary to me to go") verbs after the interrogative particle (e.g. "you walked", "did you walk?")
In some cases a limited soft mutation takes place. This differs from the full soft mutation in that words beginning with rh and ll do not mutate. Situations where the limited soft mutation occurs are as follows:
feminine singular nouns with the definite article or the number one () nouns or adjectives used predicatively or adverbially after (N.B. a verb-noun such as "going" does not change after ) adjectives following or , both meaning "so" sometimes after prefixes ending in -n or -r such as can- and dar-
The occurrence of the soft mutation often obscures the origin of placenames to non-Welsh-speaking visitors. For example, is the church of (Mary, mother of Jesus), and is the bridge on the Tawe.
Nasal mutation The nasal mutation (Welsh: ) normally occurs:
after "my" e.g. "a bed", "my bed" after the locative preposition "in" e.g. "Tywyn", "in Tywyn" after the negating prefix , e.g. "fair", "unfair".
Notes In the spoken language the possessive adjective "my" is most often heard as if spelt (i.e. ) or, in the presence of the nasal mutation, omitted all together - e.g. "my father" ( omitted), "my apple", "my sister". In the literary language, however, it is always given as : . The preposition becomes if the following noun (mutated or not) begins with m, and if the following noun begins with ng, e.g. "Bangor", "in Bangor", "Cardiff", yng Nghaerdydd "in Cardiff". In words beginning with an-, the n is dropped before the mutated consonant, e.g. + "personal" → "impersonal", although it is retained before a non-mutating letter, e.g. + "certain" → "uncertain", or if the resultant mutation allows for a double n, e.g. + "undo" → "integral". (This final rule does not apply to words that would potentially produce a cluster of four consonants, e.g. + "order" → "disorder", not *annhrefn.)
Under nasal mutation, voiced stop consonants become voiced nasals, and plain stops become voiceless nasals.
Grammatical considerations
meaning "in" must be distinguished from other uses of which do not cause nasal mutation. For example:
"he's in Bangor": has undergone nasal mutation. "he's ready": has undergone soft, not nasal, mutation. "he's singing": a verb-noun such as is not mutated. In the second and third examples, is reduced to after a vowel.
The form often used instead of after vowels does not cause nasal mutation. For example: (not *i'm ngwlad)
Aspirate mutation
The aspirate mutation () turns the voiceless plosives into voiceless fricatives. In writing, the aspirate mutation is shown by an addition of an h in the spelling (c, p, t → ch, ph, th), the resultant forms are single phonemes: ( → ).
The aspirate mutation occurs:
after the possessive adjective when it means "her" after "and" after "with, by means of" after the preposition "with" for masculine nouns after the number three () after the number six ()
Notes The aspirate mutation resulting from "her" distinguishes it from "his" (which causes soft mutation) - e.g. "her father" (as opposed to "his father"). "and" and "with, by means of" become and before vowels, respectively - e.g. "and an apple"; "don't wait". "with" becomes before a vowel and is also seen shortened to . In the spoken language, is restricted to Southern dialects (with the exception of a few set phrases) and is often replaced by or in the North depending on usage; the literary language, however, prefers the use of . Feminine nouns are preceded by the numeral , not ; does not cause mutation - e.g. "three cats", but "three dogs". The Welsh numeral becomes before a noun. This is similar to the numeral which is always before a noun - e.g. "six nations", "six mutations", "six children".
Mixed mutation
A mixed mutation occurs after the particles (before a vowel ), (before a vowel ) and (before a vowel ) which negate verbs. Initial consonants which can take the aspirate mutation do so; other consonants take the soft mutation if possible - all other consonants do not mutate. For example, "I heard" is negated as "I did not hear", "that I did not hear" and "did I not hear?", whereas "I said" is negated as , and .
In the modern spoken language, the aspirate mutation is declining and is (outside of set phrases) often omitted or replaced by the soft mutation. However, in the formal literary language (here presented) all mutations are preserved and used as expected without regional or dialectal intrusion.
Phonetic values of mutated phonemes
The true phonetic values of some of the Welsh phonemes, particularly are often debated in academia. It is often claimed that the voiceless nasals are actually aspirated . The value of Welsh is also often debated as to whether it has the underlying value or ; regardless of its underlying value, it is often heard as in the South and in the North.
The article
Welsh has no indefinite article. The definite article, which precedes the words it modifies and whose usage differs little from that of English, has the forms and . The rules governing their usage are:
When the previous word ends in a vowel, regardless of the quality of the word following, is used, e.g. ("the cat is outside"). This rule takes precedence over the other two below. When the word begins with a vowel or /h/, is used, e.g. "the bear", "the summer".. In all other places, is used, e.g. ("the boy").
The letter w represents both a consonant and the vowels and - a preceding definite article will reflect this by following the rules above, e.g. "the wall" but or "the egg". The article is also used with nouns such as in which w was formerly but is now often pronounced /w/: "the face or surface".
Pre-vocalic is used before both the consonantal and vocalic values represented by i, e.g. "the hen" and "the anguish".
The first rule may be applied with greater or less frequency in various literary contexts. For example, poetry might use more often to help with metre, e.g. "The same power is in my God" from a hymn by William Williams Pantycelyn. On the other hand, sometimes its use is more restricted in very formal contexts, e.g. "Behold, these are the ungodly" in Psalm 73.12.
The article triggers the soft mutation when it is used with feminine singular nouns, e.g. "(a) princess" becomes "the princess", but no mutation in the plural: "the princesses".
Nouns
Like most Indo-European languages, all nouns belong to a certain grammatical gender; in this case, masculine or feminine. A noun's gender conforms to its referent's natural gender when it has one, e.g. "mother" is feminine. There are also semantic, morphological and phonological clues to help determine a noun's gender, e.g. "milk" is masculine as are all liquids, "wedding" is feminine because it ends in the suffix , and "theatre" is feminine because the stressed vowel is an e. Many everyday nouns, however, possess no such clues.
Sometimes a noun's gender may vary depending on meaning, for example when masculine means "work", but when feminine, it means "occasion, time". The words for languages behave like feminine nouns (i.e. mutate) after the article, e.g. "the Welsh language", but as masculine nouns (i.e. without mutation of an adjective) when qualified, e.g. "good Welsh". The gender of some nouns depends on a user's dialect, and although in the literary language there is some standardization, some genders remain unstable, e.g. "page".
Welsh has two systems of grammatical number. Singular/plural nouns correspond to the singular/plural number system of English, although unlike English, Welsh noun plurals are unpredictable and formed in several ways. Some nouns form the plural with an ending (usually ), e.g. and . Others form the plural through vowel change, e.g. and . Still others form their plurals through some combination of the two, e.g. and .
Several nouns have two plural forms, e.g. the plural of "story" is either or . This can help distinguish meaning in some cases, e.g. whereas means both "tribe" and "load", means "tribes" and means "loads".